Tooth-crown holder.



Patented Sept. 10,1918.

Josiirii ii. ELLIOTT, oraocKroRD, ILLINOIS.

TOOTH-CROWN HOLDER.

`natalizi.

p pplication filed,V June 26, 1918. Serial No.

To all 'whom t may concern.'

Be it known that I, JOSEPH' II. EnLioT'r, a citizen of the United States, residing at Rockford, in the county of Winnebago and State of Illinois, have invented certain new and3 useful Improvements in Tooth-Crown Holders, of which the following is a specification.

This invention relates in general to dentistry tools, and has more particular reference to means for holdingl a tooth crown while filing, grinding and polishing it.

Heretofore, various forms of tooth crown holders have been provided, all of-whicli sorfar as I ain aware, are eitherv of such complicated construction as to render them impractical as a commercial product, or on the other hand, those of'simpler construetion are unsatisfactorygand ineffectivevfor general use as they are not applicable to all shapes and sizes of crowns and invariably distort the crowns whengsuilicient pressure is exerted to properly hold them.

The primary object of thepresent invention is to provide a tooth crown holder of generally improved construction and which overcomes the 'well recognized objections to those crown holders now in use. In other words, I have aimed to provide holder adapted to firmly and securely hold crowns of all shapes and sizes and with a pressure corresponding with the Awork in hand and such as not to distort the crowns, and which is exceedingly simple in construction so that it may be manufactured at a low cost iii proportion to the resultant advantages. Y

To this end, my invention in its preferred form comprehends a handle equipped with a sectional holding element or tine, the component members of which are adapted to be separated at various degrees, a single elastic tip supplied in various thicknesses, embracing both of said members and adapted when inserted in a crown to be expanded in substantially all directions by separation of the component holding members, and a simple means, such as an adjusting screw threadingly engaging one of the members and coperating with the other for separating the members to the proper degree and for holding' them in separated relation.

Referring to the drawing,

Figures l and 2 are views of different l Specification of Letters Patent.

`Patented Sept. 10,1918. 241,919.

sidesl of a dental tool provenients; l

1g. 3, anenlarged sectional view illustrating the holding' ofV a crown; i

Fig. 4, ay sectional view lon the line 4-4 of Fig.' 3; and i i ig. 5 shows three different sizes of tips, on an enlargedscale.

embodying my im-l As will readily beseen from the drawing, i

my improved tooth crown holder isof eX# ceedingly simple construction. -It comprises in the preferred embcdiment, a suitablev handle 5, which carries the i member or tine, designated generally by the character 6. In the embodimentsliown. this holding lmember is shaped tofprovide a shank 7 iixed'to the handle and. a cylindrical body .8 tapering toward its ends so as to provide a reduced holding end or tine 9 circumferentially serratedor groovedas at l1.` The shank 7 is preferablyformed with yan ends or members 14 which obviously are nor- .inallyQdisposed in closely associated relation.

By forming the shank 7 of proper resilient material, the end 14 may be sprung apart to the desired degree of separation. AIn orderV to regulate this separation toa fine degree and for holding the members 14 in the body 8 and bearing against the opposite member. It will be manifest that by turning the adjusting' screw inwardly, the members 14 will be separated, and reversing the movement, these members will spring back to their original position.

In the practice of dentistry, crowns of various thickness, shapes and sizes are required to be filled, ground and polished, and it is desired to rmly and securely hold these crowns without distorting them from their respective shapes, have required much time and expert attention in forming. It is the purpose of this invention to sheath the members 14 with a single tip of elastic material, which entirely embraces the grooved periphery 11. These tips are made of various thicknesses and ordinarily three sizes, narrow, medium and thick are suflicient for the various requirements. A tip 16 ts snugly on the members sectional holding which in many instances 14 and is retained thereon by the peripheral serrations. By reason of the :tact that this tip peripherally embraces both members 1%, there is sutiicient material in the tip so that When the latter is inserted into a crown and the members 14- separated by turning the screw 15 the elastic materials will be separated laterally in substantially all directions and will thus conform to and be firmly pressed into the irregular interior surface of the crown. By means of the screw 15, the pressure on the crown may be adjusted to a nicety and to such an extent Without distorting the crown, that the crown will be firmly and securely held and any operation may be performed thereon Without danger of the crown loosening. Vhen a smaller crown is. to be held, a correspondingly smaller tip 17 is substituted for the tip 16, and in like manner if the crown is of es pecially large size a larger tip 18 would be used. It will be especially noted that the proper tip is to be used on a given size crown so that when the members 14 arc in closed relation, the tip 16 will just tit inside the crown, and consequently, when the meinbers let are separated, the best expanding and holding action is obtained.

It is believed that the foregoing conveys a clear understanding of my improvements, and While I have illustrated the same in the preferred embodiment it should be understood that various changes might be made in the proportions and shapes of parts With- Gopies of this patent may be obtained for five cents each, by addressing the 'from the spirit and scope ot ont departing as expressed 1n the appended the invention claims:

I claim:

1. In a tooth crown holder, tion of a sectional holding element having separable holding members, an elastic sheath embracing both members and adapted to be expanded by separation of said members, and means for moving the members to vary the degree of separation and holding them in such position.

2. In a tooth crown holder, the combination of a handle, a sectional holding element ixed to the handle and comprising a pair of separable members normally disposed in close relation and having a con stant tendency when separated to return to said normal relation, an elastic sheath embracing both of said members and adapted to be expanded by separation thereof, and means on said holding element tor moving the members to vary the degree of separation and 'for holding them in such position.

3. In a tooth crown holder, the combination ot' a pair et' fingers, a single tip of elastic material embracing both ot' said lingers at one end, and an adjusting screw threadingly engaging one otl the ingers and cooperating With the other for separating the finger ends and expanding the elastic tip to the proper extent for holding a crown Within which the tij has been inserted.

JOSEPH II. ELLIOTT.

the combina- Commssioner of Patents,

Washington, D. G. 

